The ever-growing Justin Bieber fan club has two new members. Please send Red Hot Chili Peppers frontman Anthony Kiedis and legendary music producer (with an even more legendary beard) Rick Rubin their autographed poster.

In a recent chat, the rocker confessed to feeling a bit teary-eyed when he watched the Bieber documentary "Never Say Never," which takes an in-depth look at the teen's rise to fame and features him shaking his floppy hair in 3D and performing some of his biggest hits at Madison Square Garden.

One moment in particular really moved the man. "I sat on an airplane recently, coming from Hawaii to Los Angeles, with Rick Rubin just across the aisle, watching the Justin Bieber movie, 'Never Say Never.' I cried twice during that film and I want the world to know that!" he told Q magazine, via Spinner.

"They were doing this very cheesy giveaway of concert tickets to 16-year-old girls," he continued. "The cheesiness didn't matter – it was the reaction of the kids. When you saw those little girls crying deliriously, I lost it."

Tony and Ricky are only the latest members of a group of superstars that are surprising Bieber fans. Hip-hop heavyweights like RZA, Diddy, Ludacris, Kanye West and Chris Brown have stepped up and not only given props to the singer, but also, in a few cases, hooked up with him on tracks.

It's not only the music community that is all about Bieber either. Hollywood is also scrambling to bask in the glow of Biebs. Mark Wahlberg has signed on to work with Bieber on a basketball flick and, heck, even Spike Lee showed his support of the star when he appeared at the New York screening of the singer's Keidis-approved "Never Say Never."

Is it Bieber's talent, drive and undeniable charisma that have everyone so taken in with him? It must be something. Eleven million Beliebers can't be wrong.